It is well known that freshly secreted sweat is sterile and that body malodour is the result of biotransformation of the sweat by microorganisms living on the surface of the skin to produce volatile odoriferous compounds.
There are three types of material routinely used to combat body malodour: perfumes, antiperspirants and deodorants.
Perfumes typically work by simply masking body malodour.
Antiperspirants work by blocking the sweat glands, thereby reducing perspiration. However, even the best cosmetically acceptable antiperspirants rarely reduce sweat production by more than 50%.
Typical deodorants work by reducing the population of micro-organisms living on the surface of the skin, thereby reducing the extent of sweat biotransformation referred to above. Typical deodorants include ethanol and triclosan (2,4,4′-trichloro,2′-hydroxy-diphenyl ether). However, the skin is host to a number of species of microorganism, some of which are beneficial. The use of typical deodorants results in the killing of these beneficial species, in addition to the odour-producing species. This is an undesirable side effect of such deodorants.
The present invention concerns malodour reduction via the sub-lethal inhibition of certain corynebacteria, as described in WO 00/01356 (Quest International BV) and WO 00/01353 (Unilever), the latter of which is incorporated herein by reference. These prior publications disclose the sub-lethal inhibition of corynebacteria that are capable of catabolising fatty acids. Many materials are described as having this effect; however, the highly effective compositions of the present application are not disclosed.
WO 00/01353 (Unilever) uses the term “corynebacteria A” to mean corynebacteria that are able to catabolise fatty acids; this term is used with the same meaning in the present application. Such bacteria contribute strongly to the formation of body malodour, in particular axillary malodour. For many males, malodour formation is largely caused by corynebacteria A. 
The deodorants presently available on the market tend to be insufficiently effective or substantially reduce the numbers of all bacteria on the skin indiscriminately. The present invention offers the opportunity to provide cosmetic compositions, which, for many females, will substantially reduce malodour formation while inactivating only a minor portion of the skin microflora. For many males, malodour formation can be substantially reduced or even largely eliminated while inactivating only one subgroup of the skin microflora, the corynebacteria A. 
Furthermore, the specific active ingredient disclosed in the present application is effective at particularly low concentrations.
Other publications in the prior art describe alternative deodorancy methods that do not indiscriminately kill the skin microflora.
DD 29 39 58 (Medezinische Fakultaet [Charité] der Humboldt Universitaet zu Berlin) describes the use of lipoxygenase inhibitors to act biochemically to reduce sweat production or to inhibit, to various degrees, the action of skin bacteria or their enzymes on the decomposition of sweat to form unpleasant-smelling substances.
DE 43 43 265 (Henkel) describes deodorant compositions comprising saturated dioic acid (C3-C10) esters. The active inhibits a sweat decomposing esterase and the compositions are said to not disturb the skin's natural microflora.
DE 43 43 264 (Henkel) describes the use of lipid-soluble partial esters of hydroxy carboxylic acids in deodorant compositions.
U.S. Pat. No. 4,356,190 (Personal Products Co.) describes a deodorancy method utilising selected aminopolycarboxylic acids that function whilst maintaining the viability of corynebacteria. 
New deodorants containing p-hydroxybenzaldehyde or p-hydroxybenzyl alcohol are described in JP 63,292,962 (Matsushita Electric Works Ltd.).